1. Field of the Invention
This invention relates generally to monitoring fluid flow, and more particularly relates to monitoring upstream occlusion in an intravenous fluid administration system utilizing an infusion pump.
2. Description of Related Art
Fluid delivery systems for infusing parenteral fluids are commonly used in hospitals, and typically include a bottle of parenteral fluid, an infusion pump, and an intravenous (IV) set including a tubing extending from the infusion pump to a cannula at the distal end of the tubing. Such infusion pumps provide a positive means for controlling the amount of fluid administered, and are an alternative to gravitational flow systems which are readily adapted to include a drip chamber for monitoring the amount of fluid administered, and occlusion situations in the system. Detection of upstream occlusions has typically been accomplished in infusion systems utilizing peristaltic pumps through the use of an optoelectric drop detector combined with a drip chamber. The drop detector senses the occlusion by detecting the absence of drops, which may be due to a clamped or kinked upstream tubing, as well as an empty IV fluid container.
There is a need in the medical industry for elimination of such drop detectors in connection with IV infusion pump systems. An upstream occlusion can simply be detected by addition of an upstream pressure transducer, but this alternative adds considerable cost to both the instrument and the disposable portion of the IV administration set.
One solution to this problem has been to incorporate a pressure transducer in the infusion pump itself. In one such device a pressure transducer is placed in the middle of the pumping area, allowing direct measurement of pressure in the tubing segment, which is indicative of the inlet pressure. However, it would be desirable to permit detection of upstream occlusion in an intravenous fluid administration system utilizing a peristaltic pump without requiring modifications to the disposable set or the pumping mechanism itself. The present invention addresses these needs.